Improvement in slide-valves



UNITED rares (Arent trice.

CHARLES II. BRIGIITLY, OF PHILADELPHIA, PENNSYLVANIA.

IMPRGVEMENT IN SLIDE-VALVES.

To all whom it may concern Be it known that I, CHARLES H. BRIGHTLY, ofthe city and county of Philadelphia, State of Pennsylvania, haveinvented a new and Improved Slide-Valve and I do hereby declare that thefollowing is a full, clear, and exact description thereof, referencebeing had to the accompanying drawings, making a part of thisspecification, in which- Figure l is a top view of the valve applied toa steam-cylinder. Fig. 2is a vertical transverse section of the valve.Fig. 8 is a vertical longitudinal section through the valve andport-box. Fig. 4 is an enlarged horizontal section through the valve andport-box.

Similar letters of reference indicate corresponding parts in the severalfigures.

The object of my invention is to prevent a slide-valve from being forcedso hard down upon its seat by the pressure of steam in the steam-chestas to occasion much friction, by so constructing the valve that thepressure of steam upon one side will be counteracted by the pressure ofsteam upon the opposite side, as will be hereinafter described.

To enable others skilled in the art to understand my invention, I willdescribe its construction and operation.

In the accompanying drawings, A represents the valve-chest, and B arectangular slide-valve, which is arranged therein in such manner as toreceive a rectilinear reciprocating movement from a valve-rod, C, in theusual manner. D is a rectangular port-box which projects up from thebase of the valvechest as high as the vertical sides of the slidevalveB, which surrounds this box, as shown in Figs. l and 4.

The port-box D is provided with three ports or passages, a a and b,which extend laterally through it and communicate with the steamcylinderthrough steam-passages leading from the bottom of the box D, andarranged in any Suitable manner. The ports a a receive steam alternatelyfrom the steam-chest, when the valve B is reciprocated, through thelateral passages b b' b b', which are made through the longitudinalsides of the valve B, as shown in the horizontal section, Fig. 4, andthe exhaust-chamber b receives the exhaust-steam from the cylinderthrough the ports a a and side passages, l d, which latter are made inthe sides of the valve, as shown in Fig. 4.

It will be seen, by reference to the drawings, that my valve B is in theform of an elongated rectangular box having four vertical sides, g g andg g. This valve-box should be made ot'sut'ticient length to admit of itsbeing moved backward and forward the required distance to effect thealternate introduction of steam into the steam-cylinder on both sides ofthe piston. The width of this box B between the inside surfaces of thesides g g should be equal to the width of the port-box, so that thesesidesvwill work closely in contact with this box and prevent the portsfrom leaking steam. When the rectangular valve-box is applied to theelevated port-box, as I have described, the pressure of steam in thesteamchest will act on the outside surfaces of the two longitudinalplates g g, and have a tendency to press these plates against thevertical ported sides of the port-box D, but this pressure is resistedby the ends g g of the valve-box and also by a rod, E, which is tappedthrough the side g of this box, and which passes through theexhaust-port b and abuts against the inside surface of the opposite sideplate g, as shown clearly in Figs. 2, 3, and 4. This rod E acts as anintermediate brace for preventing the plates g g from collapsing attheir middle and pressing hard against the faces of the port-box. One ofthe longitudinal plates of the valve-box is applied by means ofset-screws h h, which enter transversely the ends g g and secure saidplate thereto.

By thus attaching one of the plates of the valve-box I am enabled toadjust both plates g g snugly against the surfaces ofthe port-box andcompensate for any irregularity in the impinging surfaces. In practiceadjustable bearings will be introduced into the ends of plates g g',against which the plate g will abut when set up by means of the screws hh. rlhe object of these adjustments is to enable me to make theimpinging surfaces of the plates g g and port-box parallel, so that aperfect freedom of movement will be obtained.

By my invention I conduct the live steam from the valve-chest throughboth sides of the valve-box into ports which are formed in a box that iselevated above the base of said chest, and that serves as a guide forkeeping the valve-box in place laterally. After entering this box thesteam descends below the chest and enters passages leading to thecylinder. In passing from the cylinder the exhaust-steam enters theports c a, thence passes through the side passages in the plates g ginto the port b, from which it ina-y be conducted to the atmosphere orcondenser in any desirable manner.

I have described and represented my valve as being arranged on top of ahorizontal cylinder, and consequently in a horizontal plane, but do notdesire to confine myself to such location, as the valve may be placed onthe side of a cylinder in a vertical plane7 or arranged in any otherposition. As above described, the Weight of the valve is sustained uponthe base of the valvechest, but it may bc supported upon one side of theport-box or upon the valve rod7 if the valve is differently arranged.

What I claim as my invention7 and desire to secure by Letters Patent7 isl. The arrangement ot the poi t-box D, boxvalve B B, and brace E,substantially as and for the purposes herein described.

2. The arrangement of the port-box D, boxvalve B B, screws 7L h, andscrew-threaded brace E, substantially as herein described.

3. The manner herein described of arranging the adjustingscrews h lzWith the Valve B B and port-boX D, for the purpose set forth.

CHAS. II. BBIGHTLY. lVitnesses: R. T. CAMPBELL, E. SGHAFER.

